Walter Kohn

Biography

Walter Kohn, born on March 9, 1923, in Vienna, Austria, became one of the most influential theoretical physicists and chemists of the 20th century. He attended the Akademisches Gymnasium in Vienna, but as a Jewish refugee during World War II, he had to leave Europe. He eventually ended up in Canada, studying at the University of Toronto, and later moved to the United States to complete his graduate studies at Harvard University. These early years of displacement and intense learning shaped both his personality and scientific perspective.

Kohn spent most of his academic career in the United States, working at Carnegie Mellon University, the University of California San Diego, and the University of California Santa Barbara, where he remained connected until his death. His research centered on the quantum mechanical behavior of electrons in materials, blending physics and chemistry. He was recognized for his precise mathematical skills and his knack for finding simple, elegant solutions to long-standing problems.

The highlight of Kohn's scientific work is density functional theory (DFT), which he developed in the 1960s with Lu Jeu Sham and Pierre Hohenberg. Before DFT, calculating the electronic structure of multi-electron systems meant dealing with complex many-body wavefunctions. Kohn and his colleagues showed that a system's ground-state properties could be determined from the electron density, a much simpler concept. This breakthrough revolutionized computational chemistry and condensed matter physics, making accurate calculations possible for complex molecules and solids.

In 1998, Kohn received the Nobel Prize in Chemistry, sharing it with John Pople. The Nobel Committee honored their separate but related advancements in quantum chemistry, specifically noting Kohn's work on density functional theory. That same year, he also earned the UNESCO Niels Bohr Medal and the Austrian Decoration for Science and Art. Earlier, he had won the Oliver E. Buckley Condensed Matter Prize in 1961, the Feenberg Medal in 1991, and the National Medal of Science in 1988. He later received the Harvard Centennial Medal in 2001 and the Three Physicists Prize in 2002. In 2012, the University of Vienna awarded him an honorary doctorate, and he was named a Grand Officer of the Order of Honour for Services to the Republic of Austria.

Walter Kohn passed away on April 19, 2016, in Santa Barbara, California, at 93. In his later years, he actively supported renewable energy and scientific responsibility in public affairs. He is remembered not just for his Nobel Prize-winning theory but for his wider impact on how scientists understand the quantum world of electrons.